MLA

Brodsky, Joseph, 1940-1996. Series II -- Writings -- Poetry -- Printed Collections -- Chast' Rechi -- Drafts. Box 198, folder 4300. undated. https://collections.library.yale.edu/catalog/11702341.

APA, 6th edition

Brodsky, Joseph, 1940-1996. (["Box 198, folder 4300"])(undated)[Series II -- Writings -- Poetry -- Printed Collections -- Chast' Rechi -- Drafts]. https://collections.library.yale.edu/catalog/11702341.